From 49b4589978ca181537c8ae694ac4c8d58d27a09a Mon Sep 17 00:00:00 2001 From: Dan Gohman Date: Thu, 13 May 2010 19:24:00 +0000 Subject: Add a utility function for conservatively clearing kill flags, and make use of it in MachineCSE. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103726 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/MachineRegisterInfo.cpp | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'lib/CodeGen/MachineRegisterInfo.cpp') diff --git a/lib/CodeGen/MachineRegisterInfo.cpp b/lib/CodeGen/MachineRegisterInfo.cpp index 5465fca05f..402be479ea 100644 --- a/lib/CodeGen/MachineRegisterInfo.cpp +++ b/lib/CodeGen/MachineRegisterInfo.cpp @@ -133,6 +133,15 @@ bool MachineRegisterInfo::hasOneNonDBGUse(unsigned RegNo) const { return ++UI == use_nodbg_end(); } +/// clearKillFlags - Iterate over all the uses of the given register and +/// clear the kill flag from the MachineOperand. This function is used by +/// optimization passes which extend register lifetimes and need only +/// preserve conservative kill flag information. +void MachineRegisterInfo::clearKillFlags(unsigned Reg) const { + for (use_iterator UI = use_begin(Reg), UE = use_end(); UI != UE; ++UI) + UI.getOperand().setIsKill(false); +} + bool MachineRegisterInfo::isLiveIn(unsigned Reg) const { for (livein_iterator I = livein_begin(), E = livein_end(); I != E; ++I) if (I->first == Reg || I->second == Reg) -- cgit v1.2.3